Should i call my biological Father?

My mom have always told me how my father was. She even call him once but he said it was not good timing . He told her he got married (he was married at the time i was conceived but get a divorce) and that no one knows he haves a other kid. I found his number on the internet. He been on my mind now that i have kids and they ask question about my back round and i don't know what to say. I struggling so much with actually contacting him. I find my self afraid of him rejection me. I really don't care to ever meet hem. I would like to know where i came from. He haves 4 other kids. what should i do